The present invention relates to a method and a device for evisceration of carcasses, such as pig carcasses, which are conveyed on a slaughter line suspended in gambrels or hooks, where the abdomen and breast have been cut open, the hams divided and the fat end loosened. The invention also relates to a tool for loosening the diaphragm and leaf fat, a tool and a method for cutting through the connections of the diaphragm and the intestines with the spinal column and a tool, device and method for pre-cutting the tenderloin.
The evisceration of pig carcasses is effected in a number of sub-processes, normally carried out by abattoir, i.e., slaughter house, workers. Certain of the sub-processes such as fat end loosening, brisket opening, and loosening of the diaphragm and leaf fat can be performed by various automatic or worker-operated devices.
Thus, in several abattoirs, worker-operated equipment is used to loosen diaphragm and leaf fat. The equipment, which is manufactured and marketed by Scanio, Denmark, includes a larger and a smaller hoop, which can be moved past each other by means of two pendulum-suspended cylinder units. After the intestines have been removed from the carcass, the operator makes a cut in the diaphragm muscle and positions the larger hoop under the diaphragm. The smaller hoop is moved down to meet the upper side of the diaphragm, and then the larger hoop is moved upwards in the direction of the pelvic region of the carcass. This movement loosens the diaphragm and leaf fat from the carcass. The design of the loosening equipment is shown in Danish design registration no. 63-1981 (owned by Slagteriernes Forsknings-institut, the owner of present invention).
EP-A2 0 601 812 (University of Bristol) describes a method for removing viscera from pig carcasses. The carcass is cut open at the abdomen and breast. Then, the fat end is loosened. A cutting tool with two collecting fingers is next moved along the spinal column, cutting free the intestines which fall away through the abdominal opening. The tool provides an opening in the diaphragm, through which vertical knives are inserted and moved round the inside of the carcass cutting out the diaphragm. A brush device tears out the lungs of the carcass, and finally the head is cut off. Leaf fat is not loosened or extracted. EP-A1 0 755 628 (Stork R. M. S.) describes a method for automatic releasing the intestines by means of half-hoops shaped to follow the inside of the carcass. In operative position the half-hoops practically connect to each other. The hoops are placed between the peritoneum and the abdominal wall and are moved parallel to the spinal column whereby the peritoneum with the organs arranged therein is released. The purpose of the method is to release the peritoneum almost completely from the abdominal wall with a single releasing movement. (However, the present applicant has not been able to reproduce this situation.)
Danish patent application no. 120/97, filed on Feb. 3, 1997 (also owned by Slagteriernes Forsknings-institut describes a method for the evisceration of a carcass which is suspended in a gambrel and has been cut open in the abdominal side. In this method, the diaphragm, leaf fat and intestines are loosened. The diaphragm and leaf fat are preferably loosened by means of a set of half-hoops, the free ends of which are at a substantial distance from each other, such as a set of hoops of the design known from the loosener according to the above mentioned Danish design registration. The connections between the intestines and the spinal column are cut through by the action of a cutting tool moving along the spinal column.
The object of the present invention is to provide a method which will permit mechanical loosening of leaf fat and diaphragm and the removal of the intestines and at least a part of the plucks in one piece from the carcass, whereby the need for manpower and heavy work is reduced and better hygiene is achieved than in traditional organ removal (in which the connection between the plucks and intestines is cut through inside the carcass). The method should permit much the same products to be produced as in a traditional process (i.e. a xe2x80x9ccleanedxe2x80x9d carcass, plucks, intestines, etc.). Existing transport systems for intestines and plucks should preferably be capable of incorporation in the process.
The method according to the invention, wherein the intestines of the carcass are loosened, removed and placed on a gut pan or conveyor, the diaphragm is loosened and the plucks are removed and placed on a plucks conveyor, is characterised in that the connections between the intestines and the spinal column are broken so that the intestines are made to hang out of the abdominal cavity. Further the diaphragm and leaf fat are mechanically loosened while the intestines are hanging out of the abdominal cavity and are connected to the plucks, the loosening being effected by means of a pressing device and a hoop device which can be moved independently of each other in the lengthways direction of the carcass.
In the method according to the invention the diaphragm and leaf fat are loosened without a need for cutting free and removal of the intestines as such from the carcass. Intestines and plucks can thus be removed as a single set of organs from the carcass for subsequent separation, or separation can be performed after the connection between the intestines and plucks has been pulled out of the carcass but before the connection of the plucks to, for instance, the head has been broken. It is an advantage of the method according to the invention that the diaphragm and leaf fat are removed from the carcass along with the organs.
After loosening of the diaphragm and leaf fat, the intestines and at least a part of the plucks connected to the intestines may thus be removed in one piece after being cut free from the carcass. Cutting free may be effected by 1) cutting through the trachea and oesophagus, 2) cutting free the tongue, or 3) cutting through the connection between the liver plucks and the tongue plucks, i.e. cutting through the oesophagus etc. at the level of the lungs.
Under option 1) the intestines and whole plucks are removed. The tongue remains behind in the carcass and may be removed in a subsequent manual operation. The cutting through of the trachea and oesophagus may be done before, during or after the organs attached to these tubes are loosened or freed from the inside of the carcass. Under option 2) the intestines and the whole plucks with tongue are removed. Under option 3) the intestines and only a part of the plucks are removed. The tongue plucks remain in the carcass, but can be easily removed in a subsequent manual operation, as the operator has easy access for cutting out the tongue.
In the present description the term xe2x80x9cliver plucksxe2x80x9d are preferably to be understood as the liver, diaphragm, leaf fat and kidneys. The term xe2x80x9ctongue plucksxe2x80x9d are preferably to be understood as the tongue, lungs and heart.
In connection with the removal of the intestines and plucks/liver plucks, the intestines are preferably supported by a gut pan or conveyor placed under the carcass abdomen.
When the intestines are extracted from the carcass onto a gut pan or conveyor belt, their connection with the pluck (i.e. with the whole plucks with or without tongue, or with the liver plucks) are preferably maintained, and the intestines and attached plucks are not separated until the connection between the plucks and the intestines is outside the carcass.
For loosening of the diaphragm and leaf fat, a hoop device is used which in its working position preferably has a gap at the breast opening of the carcass of such a size as to allow the passage of protruding intestines.
The position of the hollows of the fore legs/fore trotters of the carcass are preferably measured and one or more tools automatically placed in their initial and/or work positions on the basis of this measurement. Before the hoop device is inserted below the carcass diaphragm, it is preferably positioned in dependence on this measurement.
A pan may be arranged to lift protruding intestines away from the breast opening before the hoop device is inserted into the carcass under the diaphragm.
The hoop device is preferably designed to loosen the kidneys from the spinal column as it loosens the leaf fat.
The connections of the intestines and the diaphragm with the spinal column are preferably broken mechanically by means of a tool moving along the spinal column. The connections of the diaphragm and the intestines with the spinal column may be cut through by means of a tool which is substantially in the shape of a pair of tongs with closable jaws with cutting edges on the inwardly-directed sides of the jaws and a point or sharp edge on the outer edges, and which in opened position and with the jaws foremost is moved down along the spinal column to and through the diaphragm part of the carcass, whereupon the jaws are closed and the tool raised along the spinal column, thus cutting through the diaphragm part next to the spinal column and also the connections of the intestines with the spinal column.
In connection with the loosening processes, the tenderloin may also be pre-cut by means of a profiled knife moving along the spinal column to cut through the connections of the tenderloin to the spinal column. The tenderloin may subsequently easily be pulled out by an operator.
The tenderloin is preferably pre-cut by the knife being inserted against the spinal column of the carcass until it has cut into the fleshy and connective tissue on two sides of the spinal column, whereafter the knife is moved along the spinal column in the direction of the carcass head, while being pressed resiliently or yielding against the spinal column until the tenderloin is pre-cut.
The device according to the invention for the evisceration of carcasses comprises a first tool arranged to break the connections between the intestines and the spinal column, so that the intestines are made to hang out of the abdominal cavity, and a second tool arranged to loosen the diaphragm and leaf fat while the intestines are hanging out of the carcass and are connected to the plucks, the tool comprising a pressing device and a hoop device which can be moved independently of each other in the lengthways direction of the carcass.
The hoop device in its work position has preferably a gap at the breast opening of such a size as to permit the passage of protruding intestines.
The device may comprise a lifting device with a pan designed to lift the protruding intestines away from the breast opening before the hoop device is inserted into the carcass below the diaphragm.
The first tool of the device designed to break the connections of the intestines with the spinal column may substantially have the form of a pair of tongs with closable jaws, on which the inwardly directed sides may have cutting edges, while the outside has a point or cutting edge.
The device may also include a tool arranged to pre-cut the tenderloin in the carcass, and which has a knife with a profiled blade.
In particular, the device may include an arrangement for pre-cutting the tenderloin in a carcass which has a knife with a profiled blade, a knife holder with a drive unit by means of which the knife may be moved between an advanced and a retracted position in relation to the holder, said drive unit actuating the knife resiliently or yielding against the spinal column in its advanced position and a device linked to the holder which is arranged to move the tool consisting of the knife and holder in a substantially vertical direction.
The device may also include a measuring device designed to automatically determine the position of the hollows of the carcass fore legs/fore trotters (xe2x80x9carm-pitsxe2x80x9d) and to set the level of operating machines on the basis of the determinations. The measuring device may include e.g. sensor arms, linked to a position indicator and moved automatically towards and down the abdomen of the carcass, the sensor arms being arranged to send a signal to register the current signal of the position indicator at the moment the sensor arms in their movement down the carcass come into contact with the hollows of the carcass fore legs/fore trotters.
The tool according to the invention for loosening the diaphragm and leaf fat during the evisceration of carcasses comprises a hoop device designed for insertion in the carcass breast opening, which device at the breast opening has a gap of such a size as to permit the passage of protruding intestines, and that it has a pressing device working in concert with the hoop device, which pressing device can be moved independently of the hoop device in the lengthways direction of the carcass.
The gap is preferably between 3 and 20 cm, and particularly between 4 and 10 cm.
The hoop device preferably comprises two knives which in their work position are designed to make a pre-cut in the diaphragm muscle of the carcass at the breast opening.
The tool according to the invention for cutting through the connections of the diaphragm and intestines with the spinal column in the carcasses has mainly the form of a pair of tongs with closable jaws, that the inwardly directed sides of the jaws have cutting edges and that the jaws of the tongs on their outside have a point or sharp edge. The cutting edges of the inwardly directed sides will preferably form a xe2x80x9cVxe2x80x9d in the closed state of the jaws.
A drive unit may be arranged to move the legs of the tongs between an open position in which the jaws are at a distance to each other and a closed position in which the jaws are together.
The method according to the invention for cutting through the connections of the diaphragm and intestines with the spinal column in carcasses includes moving a tool, in the form of a pair of tongs with closable jaws which has cutting edges on the inwardly directed sides of the jaws and a point or sharp edge on the outside, in open state with the jaws foremost down to and through the diaphragm part of the carcass adjacent to the spinal column, closing jaws of the tool, and then moving the tool up along the spinal column, whereby the diaphragm part adjacent to the spinal column and the connections between the intestines and the spinal column are cut through by the tool.
The tool according to the invention form pre-cutting the tenderloin in a carcass comprises a knife with a profiled blade.
The tool may further comprise a holder which has a drive unit connected to the knife by means of which the knife can be moved between an advanced and a retracted position in relation to the holder, the unit being resilient or yielding in the advanced position of the knife. The knife may be fixed to the holder by means of a hinge part and the drive unit may be mounted between the holder and the knife at a distance from the hinge part.
The blade is preferably bent at an angle, or at the least the central part of the blade may be curved, preferably as a circular arc.
The holder preferably has a stop face arranged in front of the knife seen in its direction of movement when pre-cutting the tenderloin from the spinal column.
Preferably the holder has a contact face arranged in front of the knife and lying substantially perpendicular to the knife""s direction of movement during pre-cutting.
The device according to the invention for pre-cutting the tenderloin of carcasses comprises a knife with a profiled blade, a knife holder with a drive unit by means of which the knife can be moved between an advanced and a retracted position in relation to the holder, the unit begin resilient or yielding in the advanced position of the knife, and a device attached to the holder which is arranged to move the tool comprising the knife and holder in a mainly vertical direction.
The device may be arranged to halt its movement in the mainly vertical direction when the tool moving in the vertical direction meets an obstruction excerting a greater reaction force than its pre-cutting force (i.e. when it meets the diaphragm).
The method according to the invention for pre-cutting the tenderloin of carcasses includes moving a knife with a profiled blade in against the spinal column of the carcass until it has cut into the fleshy and connective tissue on two sides of the spinal column, moving the knife along the spinal column in the direction of the carcass head, while being pressed against the spinal column in a resilient or yielding way, and that continuing movement along the spinal column until the tenderloin is pre-cut.
The knife may be moved while mounted on a holder with a stop face, and the movement along the spinal column may continue until the stop face meets resistance from the carcass diaphragm.
The knife may be moved to its retracted position after pre-cutting and in its retracted position continue its movement along the spinal column while tools carries out processing operations on the carcass viscera.
Pre-cutting of the tenderloin is preferably started after the intestines have been loosened from the carcass spinal column and are hanging out of the abdominal cavity.
A preferred embodiment of the method consists of the diaphragm and leaf fat of the carcass being loosened directly after the knife has concluded pre-cutting along the spinal column. To carry out the loosening a hoop device is preferably used with an internal diameter sufficiently large to permit the hoop device to pass the knife and associated pressing device when the hoop device is moved up to the rear end of the carcass.
The invention is mainly described in connection with the evisceration of pig carcasses. The invention may however be applied to carcasses from other animals, such as cattle (including cows, heifers, calves and bulls), sheep and goats.